1. Field of the Invention
The present invention relates to a network system and a store and forward machine associated with this network.
2. Description of the Prior Art
Recently, there has been known a network system which consists of a plurality of store and forward machines, and each store and forward machine includes at least one facsimile terminal and serves as a node of the network.
FIG. 1 is a schematic drawing showing one example of this kind of network system. A plurality of communication terminals 1 are connected to a store and forward machine 2, so that the store and forward machine 2 can administrate these associated communication terminals 1. And, this store and forward machines 2 is connected to a common network 3 as a node, so that communication (i.e. inter-exchange or transmission) between any nodes can be carried out through this network 3.
FIG. 3 is an example of a communication terminal administration table utilized in the store and forward machine 2 for administrating communication terminals 1, in which all the identification numbers of communication terminals 1 and their network addresses (for example, telephone numbers) are listed up in a table.
In a network system constituted as described above, all the communication terminal administration table must be identical with each other for inherent communication purpose. Therefore, if any change including addition and deletion with respect to a certain communication terminal 1 occurs, it is mandatorily required to correct not only a communication terminal administration table in one specific store and forward machine 2 which administrates above certain communication terminal 1 causing the change, but also other communication terminal administration tables stored in all the remaining store and forward machines 2.
To correct a content of each communication terminal administration table in accordance with certain changes, each store and forward machine 2 is equipped with a console 22 so that an operator can change the content of the administration table.
However, as the network system expands its scale, the number of the store and forward machines 2 increases correspondingly. Therefore, correcting works by operators become nuisance as a whole and, thus, it becomes difficult to adopt above method as a routine method.
In view of such circumstances, Japanese Laid-open Patent Application No. HEI 1-166643 proposes a system shown in FIG. 4 in which a central administration apparatus 4 is newly provided as a node, so that all the data in the communication terminal administration tables of respective nodes can be automatically renewed in response to a changing operation by the central administration apparatus 4.
However, even in such a system, the correcting work cannot be so facilitated as expected, because the correcting work itself, if concentrated to the central administration apparatus 4, would become a fairly large amount. And also, in view of simplification of the system, it is not desirable to install the central administration apparatus 4 in addition to store and forward machines 2.